From owner-cvs-all@FreeBSD.ORG Thu Oct 2 20:50:30 2003 Return-Path: Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A485216A4B3; Thu, 2 Oct 2003 20:50:30 -0700 (PDT) Received: from repoman.freebsd.org (repoman.freebsd.org [216.136.204.115]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3053543FF2; Thu, 2 Oct 2003 20:50:30 -0700 (PDT) (envelope-from marcel@FreeBSD.org) Received: from repoman.freebsd.org (localhost [127.0.0.1]) by repoman.freebsd.org (8.12.9/8.12.9) with ESMTP id h933oUXJ025747; Thu, 2 Oct 2003 20:50:30 -0700 (PDT) (envelope-from marcel@repoman.freebsd.org) Received: (from marcel@localhost) by repoman.freebsd.org (8.12.9/8.12.9/Submit) id h933oTOv025746; Thu, 2 Oct 2003 20:50:29 -0700 (PDT) (envelope-from marcel) Message-Id: <200310030350.h933oTOv025746@repoman.freebsd.org> From: Marcel Moolenaar Date: Thu, 2 Oct 2003 20:50:29 -0700 (PDT) To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org X-FreeBSD-CVS-Branch: HEAD Subject: cvs commit: src/sys/ia64/ia64 machdep.c syscall.S vm_machdep.c X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Oct 2003 03:50:30 -0000 marcel 2003/10/02 20:50:29 PDT FreeBSD src repository Modified files: sys/ia64/ia64 machdep.c syscall.S vm_machdep.c Log: Swap the syscall caller frame info (i.e. the return pointer and frame marker) and the syscall stub frame info in the trap frame. Previously we stored the stub frame info in (rp,pfs) and the caller frame info in (iip,cfm). This ends up being suboptimal for the following reasons: 1. When we create a new context, such as for an execve(2), we had to set the (rp,pfs) pair for the entry point when using the syscall path out of the kernel but we need to set the (iip,cfm) pair when we take the interrupt way out. This is mostly just an inconsistency from the kernel's point of view, but an ugly irregularity from gdb(1)'s point of view. 2. The getcontext(2) and setcontext(2) syscalls had to swap the (rp,pfs) and (iip,cfm) pairs to make the context compatible with one created purely in userland. Swapping the (rp,pfs) and (iip,cfm) pairs is visible to signal handlers that actually peek at the mcontext_t and to gdb(1). Since this change is made for gdb(1) and we don't care about signal handlers that peek at the mcontext_t because we're still a tier 2 platform, this ABI breakage is academic at this moment in time. Note that there was no real reason to save the caller frame info in (iip,cfm) and the stub frame info in (rp,pfs). Revision Changes Path 1.157 +5 -11 src/sys/ia64/ia64/machdep.c 1.8 +30 -26 src/sys/ia64/ia64/syscall.S 1.72 +2 -3 src/sys/ia64/ia64/vm_machdep.c